Torque wrench adapter

ABSTRACT

A HOLDING DEVICE CLAMPING TO AN ORDINARY BOX END WRENCH AND DRIVABLY CONNECTED TO A TORQUE WRENCH. THE HOLDING DEVICE HAS A BASE CARRYING A PLURALITY OF CLAMP MEMBERS OPERABLE TO CONNECT THE BOX END WRENCH TO THE BASE. A GUAGE ROD, SECURED TO ONE END OF THE BASE, IS USED TO LOCATE THE BOX END WRENCH ON THE BASE, WHEREBY THE TORQUE WRENCH IS USED IN COMBINATION WITH THE BOX END WRENCH TO TIGHTEN A NUT WITH A SELECTED TORQUE.

United States Patent 2,492,470 12/1949 Iarkas Inventor Allen E. Newherg St. James, Minn. 882,635

Dec. 5, 1969 June 28, 1971 Appl. No. Filed Patented TORQUE WRENCH ADAPTER 10 Claims, 4 Drawing Figs.

References Cited UNITED STATES PATENTS 7 3/ l 39UX FOREIGN PATENTS 993,128 7/1951 France 73/139 89,060 10/1891 Germany 73/139 Primary Examiner-Charles A. Ruehll Att0rney-Burd, Braddock and Bartz ABSTRACT: A holding device clamped to an ordinary box end wrench and drivably connected to a torque wrench. The holding device has a base carrying a plurality of clamp members operable to connect the box end wrench to the base. A gauge rod, secured to one end of the base, is used to locate the box end wrench on the base. The torque wrench is drivably connected to the base, whereby the torque wrench is used in combination with the box end wrench to tighten a nut with a selected torque.

PATENTEU JUH28 |97| ATTORNEYS TORQUE WRENCH ADAPTER BACKGROUND OF INVENTION The ordinary torque wrench has a male drive member to receive a socket of a proper size to fit over the nut to be tightened. In some machines, some bolts and nuts are placed in such a location that special types of torque wrenches and sockets and like tools must be used to properly tighten the bolts and nuts. These special tools add to the expense and time required to repair a machine. In the repairing of machines, the proper size socket is often not handle or readily available and the bolt or nut which is to be tightened cannot be easily reached with an ordinary socket wrench. These disadvantages of special tools have been obviated by applicant's torque wrench adapter.

SUMMARY OF INVENTION The invention relates to an adapter or holding means for coupling a conventional torque wrench to an open end or box end wrench for tightening a threaded member, as a bolt or nut. The adapter has a base carrying clamp means operable to clamp the box end wrench to the base. Secured to the base is a gauge means for fixing the location of the box end wrench relative to the base so that the box end wrench has a known torque arm. The torque wrench and base have coacting means which drivably couple the torque wrench to the base, whereby the torque wrench can be used to tighten the threaded member with a selected torque readable on the torque wrench.

An object of the invention is to provide a torque wrench adapter which is lightweight, sturdy in construction, easy to use, and economical in cost. Another object of the invention is to provide a torque wrench adapter which can be mounted on all types of open end and box end wrenches. Still another object of the invention is to provide a torque wrench adapter which can use the conventional torque wrench to apply a predetermined torque on a threaded fastener through an open end or box end wrench.

IN THE DRAWINGS FIG. 1 is a plan view of the torque wrench adapter of the invention coupling a conventional torque wrench with a box end wrench;

FIG. 2 is an enlarged plan view of the bottom of the torque wrench adapter of FIG. 1 with the torque wrench and box end wrench removed;

FIG. 3 is a sectional view taken along the line 3-3 of FIG. 2; and

FIG. 4 is an enlarged sectional view taken along the line 4-4 of FIG. 1.

Referring to the drawings, there is shown in FIG. 1 a torque wrench, indicated generally at 10, operatively coupled to a box end wrench 11 with the adapter or holding device 12 of the invention. The torque wrench has a head 13 carrying a downwardly projected male drive member 14. The drive member 14 has a generally square cross sectional shape. Drive member 14 can have other noncircular shapes. Secured to the head 13 is an elongated linear arm 15. The outer end of the arm is attached to a handle 16. Located parallel with the arm 15 is a pointer 17 having an end located adjacent a transverse scale 18 positioned adjacent the handle 16. The wrench 10 is a conventional torque wrench which is normally used with a socket to tighten a threaded member, as a nut or bolt.

The box end wrench 11 is an elongated generally flat body 19 terminating in an open end 21. The opposite end of the wrench 11 has a box end 22 drivably positioned about a threaded member or nut 23. The nut is threaded on a bolt 24. The nut and bolt can be the head of a bolt that extends into a threaded hole.

FIG. 2 shows the adapter 12 having a generally flat rectangular base 26. Base 26 is a flat rectangular metal plate. The midportion of the base has a square hole 27. The hole 27 is of a size to receive the square male drive member 14 of the torque wrench, whereby the torque wrench is drivably coupled to the base 26. The hole 27 can have other noncircular shapes to drivably receive the drive member of the torque wrench. Located on opposite diagonal corners of the base are holding or clamp means, indicated generally at 28 and 29, for attaching the wrench 11 to the base 26. The clamp means 28 comprise an upwardly directed threaded stud 31 anchored in one comer of the base 26. As shown in FIG. 3, the stud 31 projects upwardly and outwardly at a slight angle 33 from the vertical. The angle is approximately 7 to l0 from the line perpendicular to the flat top or face of the base 26. The stud 31 may have other angles and still achieve the holding or clamping action of the clamp means. Threadably located on the stud 31 is a nut 33 carrying an outwardly directed or lateral leg 34. As shown in FIG. 3, the leg 34 is secured to the nut at a slight angle so that the leg 34 is substantially parallel to the top surface of the base 26 when the leg 34 is in a transverse position across the base. As shown in FIG. 4, when the leg 34 has been rotated out of the transverse position, the leg moves circumferentially and at a downward angle to engage and clamp the body 19 of the box end wrench to the base 26.

The clamp means 29 has a similar angularly disposed stud 36 carrying a nut 37. An outwardly directed or lateral leg 38 is attached to the side of nut 37. Stud 36 is located in the opposite diagonal corner of the base 26', and extends upwardly and outwardly in an opposite direction from the stud 31. The legs 34 and 38 project from their nuts 33 and 37 to the opposite side of the base. In other words, the legs 34 and 38 extend transversely across the base 26. The legs 34 and 38 can be viewed as projections or wings attached to members threaded on studs 31 and 37.

Projected longitudinally from one end of the base 26 is a linear guide rod 39 having an end 41. The guide rod 39 is attached to the base 26 toprovide a fixed distance between the end 41 of the center of the hole 27. As shown in FIG. 3, the rod 39 extends into a hole 42 at the end of base 26. A trans verse fastener 43, as a split ring, set screw or the like, located transversely of the hole 42, is used to hold the rod 39 in assembled relation with the base 26. The length of rod 39 can vary to change the distance between the end of rod 39 and the center of hole 27. Rod 39 extends from the right side of base 26 so that end 41 will drag on the nut'23.

In use, the box end wrench 19 is mounted on the base 26 with the box end 22 located in general alignment with the end 41 of the gauge rod 39. This fixes the effective torque arm of the box end wrench. This torque arm is equal to the distance between the hole 27 and the end 41. In one form of the invention, this distance is 4 :4 inches, and the torque wrench is about 19 inches long. When this dimension is used, the conventional 19 inch torque wrench will show percent of the torque being applied to the threaded member. A conventional torque wrench has a scale which shows the number of foot pounds directly. Since the adapter makes the torque wrench longer by the length of a portion of the box wrench, the effective torque of the torque wrench is increased. With 80 percent of the torque being applied, as shown on the scale, there would be an increase of approximately 20 percent on the threaded member. In other words, if the scale would read 80 foot pounds, the torque on the threaded member would be foot pounds.

The box end wrench 11 is attached to the adapter 12 by the use of the clamp means 28 and 29. These clamp means function to clamp the wrench 11 to the adapter 12. Initially, the nuts 33 and 37 are turned onto the studs 31 and 36, respectively, until the legs 34 and 38 are spaced from the top of the base 26 a distance substantially equal to the thickness of the body 19 of the box end wrench 11. The legs are positioned in their transverse positions, as shown in FIG. 3, so that the body 19 of the wrench can be placed under the legs 34 and 38. As shown in FIG. 4, the body 19 is located under leg 34. Leg 34 is substantially parallel to the top of the base 26 so that the body 19 can fit between the leg 34 and the base 26. The body 19 is located in engagement with the stud 31, as well as the stud 36.

The hole 27, being located between the legs 34 and 38 is the center of rotation of the base. The legs 34 and 38 transmit force to opposite sides of the wrench body 19. The legs 34 and 38 are then circumferentially turned to angular positions, as shown in FIG. 1. As each leg is turned, it moves circumferentially and in a downward direction to clamp the body 19 tightly to the base 26. The slight downwardly directed angle of each leg 34 and 38 wedges the body 19 into engagement with the studs 31 and 36.

The torque wrench is drivably attached to the base 26 by inserting the square male drive member 14 into the hole 27. The torque wrench 10, in combination with the box wrench 11, can be used to tighten nuts or bolts, as on an engine head, to a certain degree of tightness measured in foot pounds. The scale on the torque wrench 10 shows the number of foot pounds. The increase in the effective length of the torque wrench requires an adjustment in the reading of the scale. This adjustment is proportional to the ratio of the length of the torque wrench to the length of the distance between the hole 17 and the gauge rod end 41. In the aforesaid specific example of this invention, the scale will show 80 percent of the torque being applied to the nut. A torque reading of 80 foot pounds would actually be 100 foot pounds on the nut 23. Other torque arm ratios can be used. in box end or open end wrenches having a body length of less than 5 inches, a shorter gauge rod can be used. This will change the effective length of the torque arm of the torque wrench so that an appropriate adjustment of the reading must be made to determine the actual foot pounds of torque being applied to the nut or other threaded member.

While there have been shown and described preferred embodiments of the invention, it is understood that various changes in the materials, clamping means, gauge means, and the connection between the adapter and the torque wrench may be made by those skilled in the art without departing from the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

I claim:

1. A holding device for coupling a first wrench to a second wrench comprising: a base member, clamp means on the base member for mounting the first wrench on the base whereby the base member and first wrench can be moved together,

drive means on the base connectable with the second wrench whereby the second wrench is usable to move the base member and first wrench mounted thereon.

2. The device of claim 1 wherein: the second wrench is a torque wrench having a drive member coating with the drive means of the base member whereby the torque wrench is used with the first wrench to apply a determined amount of force to a threaded member.

3. The holding device of claim 1 wherein: the clamp means comprise a pair of spaced threaded studs extended upwardly from the base member, and nut means having a laterally directed leg threaded on each stud, said leg, upon rotation of the nut means, engageable with the first wrench to hold the first wrench on the base member.

4. The holding device of claim 3 wherein: the studs are located on opposite diagonal portions of the base member and are inclined in opposite outward directions.

5. The holding device of claim 4 wherein: said legs, when located transversely of the base member, are substantially parallel to the face of the base member adjacent the legs.

6. The holding device of claim 1 wherein: the base member is a generally flat plate, said drive means comprising a noncircular hole for receiving a male drive member of the second wrench.

7. The holding device of claim 1 including: gauge means on the base member usable to locate the first wrench in a predetermined position on the base member.

8. The holding device of claim 7 wherein: the gauge means is a rod longitudinally projected outwardly from one end of the base member.

9. The holding device of claim 1 wherein: the base member is a generally flat plate, said clamp means comprising a pair of threaded studs secured to diagonally opposite portions of one face of the plate, said studs extended outwardly away from the one face of the plate, and nut means having a laterally directed leg threaded on each stud, said leg, upon rotation of the nut means, engageable with the first wrench to hold the first wrench on the base member and gauge means projected from one end of the plate usable to locate the first wrench in a predetermined position on the base member.

10. The holding device of claim 9 wherein: each stud is inclined in an upward and outward direction.

gz g UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION t n N 3 .587 .307 Dated June 2 E71 :[nvento -(s) Allen E. Newherg It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 11, "handle" should be handy- Column 2, line 36, "of" (first occurrence) should be --and-.

Column 2, line 49, "4 1/4" should he --4 3/4--.

Column 3, line 21, "17" should be 27- Column 4, line 5, "coating" should he coacting-.

Signed and sealed this 28th day of December 1 971 (SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHELK Attesting Officer Acting Commissioner of Patents 

